Ianto stares at the other man for a long second. Letting himself float. He supposes he should have seen this coming, all things considered. He supposes that there's nothing for him to truly be afraid of in such a situation either, considering the fact that his feet do still touch the ground and John is still right there. All the same, he can feel the tension in his body rising even at just the thought of it.

"Floating," Ianto repeats, before glancing around them at the water itself. "You do realize that this is what amounts to a communal bath, yeah? And you're trying to teach me swimming techniques in it?" It's a weak argument, he knows. It's the first thing that comes to his mind at the thought of trying to lay back and float in the water, though. All the same, he doesn't let go of the other man's hand or step back to shallower water.